Originally Posted by Bahia
I am about the rewire my electrical system
on the boat (both AC & DC).
I have 2 engines and a genset.
I am planning to have 1 house bank
3 separate starter batteries
Hello, there's no need for 3 starter batteries which for 99% of the time are going to just sit there and do nothing. I would just use one and use the space for extra house batteries.
Starting an engine doesn't take much out of the battery so rewire the alternators to go to the house batteries and use the voltage sensitive relay to combine the house and starter banks. Wiring
this way the relay won't carry alot of amps to charge the house bank. If the alternators are connected and can be isolated via the house battery switch then add some stranded relays to disable the ignitions for the engines - this way you won't start the engine without the alternators been connected to a battery.
I would also use a bus bars to reduce the amount of connections on the batteries.
Multiple alternators are okay to be connected together, batteries will only take the current they need. However if you have a small house bank and large amp alternators it may be better to wire one alternator (the smallest if different) to the start battery.
Let me know if a wiring
diagram would help on my suggestion.